This is the 35 USC 371 national stage of International Application PCT/FR98/01426 filed on Jul. 3, 1998, which designated the United States of America.
The present invention relates to an electric household appliance for the processing of foods, of the type particularly, but not exclusively, of the food processor type, which comprises a housing enclosing an electric motor group and having a region forming a base whose upper surface is traversed by the output shaft of the motor group, and a bowl removably locked on the base of the housing, closed to lock with a removable cover, and receiving a working tool adapted to be driven in rotation by the motor shaft.
It relates more particularly to an apparatus of this type which moreover comprises a safety device comprising a switch arranged in the supply circuit of the motor, a pusher mounted vertically slidably in a recess provided over all the height of the peripheral wall of the bowl, whose lower end is disposed in alignment with an opening provided in the periphery of the base of the housing, when the bowl is locked on the base, and whose upper end is adapted to be actuated by a cam carried by the cover, when this latter is locked on the bowl in place, such that the pusher is lowered into the opening in the base, as well as a control mechanism disposed in the housing, actuated by the pusher when it is pushed down into said opening, and controlling the opening of the switch to permit controlling the closure of the switch to permit supply of the motor.
It is known that in such apparatus, it is important to avoid any contact of the hand with the rotating working tool, constituted generally by a slicing tool considered dangerous, so as to prevent accidents and, to this end, the safety device of the above type with which the apparatus is provided is adapted to permit the operation of the motor only when the bowl is locked on the base of the housing, and when this bowl is itself locked by the cover.
In an electrical household appliance provided with a known safety device of this type, as described in FR-A-2 472 925, the opening of the base adapted to the passage of the pusher opens outwardly when the bowl is not in place on the base, and is closed in its lower portion by a flexible deformable membrane which is maintained by a lip formed on the internal surface of the base, such that during locking of the cover on the bowl once in place on the base, the cam carried by the cover actuates the pusher which is then pushed down into the opening of the base, which pusher stretches the membrane and acts on the control mechanism of the switch to cause closing of the electrical supply circuit of the motor. However, this flexible membrane itself constitutes a costly member, difficult to emplace, adapted to come off, and subject to deterioration with time, even to be torn by the repeated stretching under the action of the pusher, thus rendering the apparatus unusable. Moreover, the opening of the base being outward, and hence visible, when the bowl is not in place, the latter tends to attract the attention, in particular of a child, and thus lead to accidental starting of the motor by stretching of the membrane with any object introduced into this opening. Moreover, this opening in the base forms a food trap which is therefore apt to frustrate the control of the switch, and which is difficult to clean.
The invention particularly has for its object to overcome these drawbacks and to provide an electrical household appliance, of the type described above, in which the safety device operates perfectly and with high reliability.
According to the invention, the safety device comprises moreover a rigid piece forming a cover which is movably mounted on the upper surface of the base of the housing between a rest position to which it is automatically brought when the bowl is not in place on the base and in which it masks the opening of the base, and an active position in which it is moved under the action of an actuating member carried by the bowl upon locking the latter on the base and in which it uncovers the opening of the base so as to permit passage of the pusher.
Thus, this rigid cover constitutes thereafter a truly robust mechanical piece, and hence is reliable, simpler, lost costly, easy to make and perfectly adapted to mass production. Moreover, the opening in the base being masked automatically by the cover in the rest position, when the bowl is not in place, this cover constitutes itself a member adapted to dissuade any child from having access to the control mechanism of the switch, and hence accidentally to start the motor, which especially increases the safety of the device. This increase in safety is the more justified as the movement of the cover permits uncovering the opening of the base which is itself subjected to the locking of the bowl on the base.
According to a preferred embodiment, the cover is horizontally slidably mounted, in a direction transverse to the vertical axis of the motor shaft, in a recess which is provided in the upper surface of the base extending to the peripheral edge of said base, and into which opens the opening of the base, said cover being slidably mounted the action of a return spring which tends to return it to the rest position.